Liquid-cooling device

ABSTRACT

A liquid-cooling device includes a heat exchanger defining a cavity therein and a liquid-guiding component received in the cavity. The liquid-guiding component includes a body and a fixing portion extending from the body and fixed to the heat exchanger. A first liquid passage is defined through the body and a second liquid passage is formed between the body and an inner sidewall of the heat exchanger surrounding the cavity. The first liquid passage is in fluid communication with the second liquid passage via a bottom of the cavity. An outlet and an inlet are formed at an end of the liquid-guiding component and in fluid communication with the first and second liquid passages. Liquid flows in the cavity of the heat exchanger via the first liquid passage and has a sufficient contact with the inner sidewall of the heat exchanger.

BACKGROUND

1. Technical Field

The present disclosure relates generally to cooling devices and, more particularly, to a liquid-cooling device for dissipating waste heat generated by electrical or electronic components and assemblies.

2. Description of Related Art

Nowadays, various cooling devices are used to remove heat from electrical or electronic components which generate a large amount of heat during operation. Metallic heat sinks with fins, heat exchangers utilizing phase-change, or liquid cooling devices are in most common use.

A typical liquid cooling system comprises a heat absorbing unit for absorbing heat from a heat source, and a heat dissipating unit which defines a cavity filled with liquid. The liquid conducts heat exchange with the heat absorbing unit, thereby taking away the heat from the heat absorbing unit when the liquid is circulated. However, when the liquid directly flows in the cavity of the heat dissipating unit without any liquid-guiding component, the liquid only produces a smooth flowing in the cavity along inner surfaces of the heat dissipating unit. The liquid fails to sufficiently contact with the inner surfaces of heat dissipating unit and heat exchanger between the liquid and the inner surfaces of the heat dissipating unit is limited. Accordingly, the liquid cooling system has a lower work performance.

What is needed, therefore, is a liquid cooling device which has a high work performance.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages and novel features of the disclosure will become more apparent from the following detailed description of an embodiment/embodiments when taken in conjunction with the accompanying drawings.

FIG. 1 is an isometric, assembled view of a liquid-cooling device in accordance with a first embodiment of the present disclosure.

FIG. 2 is a view similar to FIG. 1, wherein a part of the liquid-cooling device is cut off for clarity.

FIG. 3 is an exploded view of the liquid-cooling device of FIG. 1.

FIG. 4 is an exploded view of a liquid-cooling device in accordance with a second embodiment of the present disclosure.

FIG. 5 is an isometric view of the liquid-cooling device of FIG. 4, wherein a part of the liquid-cooling device is cut away for clarity.

FIG. 6 is an isometric view of a liquid-cooling device in accordance with a third embodiment of the present disclosure, wherein a part of the liquid-cooling device is cut away for clarity.

FIG. 7 is an exploded view of the liquid-cooling device of FIG. 6.

DETAILED DESCRIPTION

Referring to FIGS. 1-3, a liquid-cooling device in accordance with a first embodiment of the disclosure is especially useful in efficiently dissipating heat from a heat generating component (not shown), and more particularly to a part of the heat generating component, which is located at a lower position. The liquid cooling device comprises a heat exchanger 10 and a liquid-guiding component 30 engaged with the heat exchanger 10.

Particularly referring to FIGS. 2-3, the heat exchanger 10 is made of thermally conductive material such as copper or aluminum, and substantially T-shaped in profile having a large top surface and a small bottom surface. The heat exchanger 10 comprises a base plate 11 having a large top surface and a heat-absorbing portion 12 protruding downwardly and perpendicularly from a center of a bottom surface of the base plate 11. The base plate 11 is used for holding a pump (not shown) thereon. The heat-absorbing portion 12 has a column-like configuration with a rectangular cross section, although it is not limited to such configuration and cross section. The heat-absorbing portion 12 comprises a small bottom surface (not labeled) used for contacting the heat generating component (not shown). The heat-absorbing portion 12 defines a cylindrical cavity 120 in a center thereof and the base plate 11 defines an annular slot 14 surrounding and communicating with the cavity 120. An annular inner sidewall defining the slot 14 is adjacent to an annular inner sidewall defining the cavity 120. The slot 14 is configured for engaging the liquid-guiding component 30. The cavity 120 is provided for filling the liquid therein. A protrusion 16 extends horizontally and inwardly from the inner sidewall defining the slot 14, for facility of an external tool (not shown) to operate on the liquid-guiding component 30.

The liquid-guiding component 30 comprises a hollow cylindrical body 32 and an annular flange 34 surrounding the body 32. The body 32 defines a first liquid passage 100 therethrough and an upper outlet 320 communicating with the first liquid passage 100. An outer diameter of the body 32 is less than a diameter of the cavity 120 of the heat-absorbing portion 12, whereby a second liquid passage 200 is defined between an outer sidewall of the body 32 of the liquid-guiding component 30 and an inner sidewall of the heat-absorbing portion 12. A bottom end of the body 32 is spaced from a bottom of the cavity 120, whereby the second liquid passage 200 is communicated with the first liquid passage 100. The flange 34 extends horizontally and outwardly from an outer circumference of the body 32. The annular flange 34 has an outer diameter similar to that of the annular slot 14, thereby an edge of the annular flange 34 abutting against the inner sidewall of the base plate 11 around the annular slot 14 to firmly secure the liquid-guiding component 30 to the heat-absorbing portion 12. The annular flange 34 defines a plurality of inlets 340 communicating with the second liquid passage 200, and located around a circumference of the body 32. The inlets 340 are ached-shape and evenly distributed in the annular flange 34 around the body 32. The outlet and inlets 320, 340 are connected to the pump (not shown) via conduits (not shown) to construct a flow circulation for the working liquid. The annular flange 34 defines a cutout 342 in an outer edge thereof, corresponding to the protrusion 16 of the heat exchanger 10.

In operation of the liquid cooling device, the bottom surface of the heat-absorbing portion 12 of the heat exchanger 10 absorbs heat from the heat generating component. The heat in the bottom of the heat-absorbing portion 12 is upwardly transmitted to the top of the heat-absorbing portion 12 along the sidewalls of the heat-absorbing portion 12. Liquid enters the second liquid passage 200 through the inlets 340 of the liquid-guiding component 30 to sufficiently contact the inner sidewalls of the heat-absorbing portion 12 and an inner surface of the bottom of the heat-absorbing portion 12. The liquid then flows into the first liquid passage 100 through the bottom of the heat-absorbing portion 12 and finally leaves the body 32 of the liquid-guiding component 30 from the outlet 320 to take away the heat in the heat-absorbing portion 12.

Since the liquid-guiding component 30 guides the liquid to flow along the inner sidewalls of the heat-absorbing portion 12 towards the bottom of the heat-absorbing portion 12 in the second liquid passage 200, the liquid can have a sufficiently contacting area with the inner sidewall of the heat-absorbing portion 12. The heat in the inner sidewalls of the heat-absorbing portion 12 can be quickly taken away by the liquid, whereby heat exchange efficiency between the inner sidewalls of the heat-absorbing portion 12 and the liquid is improved to quickly cool the heat generating component attached to the bottom of the heat-absorbing portion 12.

Referring to FIGS. 4-5, a liquid-cooling device in accordance with another exemplary embodiment of the disclosure is shown. The difference between this embodiment and the previous embodiment is that the liquid cooling device comprises a heat exchanger 50 and a liquid-guiding component 40 engaging with the heat exchanger 50. The heat exchanger 50 comprises a base plate 51 and a heat-absorbing portion 52 protruding downwardly and perpendicularly from the base plate 51. The base plate 51 defines an annular slot 54 around the heat-absorbing portion 52. The heat-absorbing portion 52 defines a plurality of annular grooves 520 in an inner sidewall along a circumference thereof, for increasing a contacting area between the liquid and the inner sidewall of the heat-absorbing portion 52. The liquid-guiding component 40 comprises a hollow cylindrical body 42 defining an outlet 420 at a top end thereof. The first liquid passage 100 is defined through the body 42 of the liquid-guiding component 40. The second liquid passage 200 is defined between an outer sidewall of the body 42 of the liquid-guiding component 40 and the inner sidewall of the heat-absorbing portion 52. The fixing portion, such as a fixing plate 44 extends horizontally and outwardly from an outer edge of the body 42. A plurality of spaced tongues 440 extends horizontally and outwardly from an outer edge of the fixing plate 44. The fixing plate 44 has a thickness smaller than a depth of the annular slot 54 and an outer diameter smaller that of the annular slot 54, thereby defining an inlet 430 between the inner sidewall of the base plate 51 and the outer edge of the fixing plate 44. A third liquid passage 300 is defined between a lower surface of the fixing plate 44 and a bottom of the annular slot 54. The third liquid passage 300 is communicated with the inlet 430 and the second liquid passage 200.

In operation, the liquid firstly enters the third liquid passage 300 via the inlet 430, flows towards the second liquid passage 200 to sufficiently contact the inner sidewalls of the heat-absorbing portion 52, flows into the first liquid passage 100 through a bottom of an inside of the heat-absorbing portion 52, then leaves the body 42 of the liquid-guiding component 40 from the outlet 420 to take away heat in the heat-absorbing portion 52.

By provision of the annular grooves 520, a roughness of the inner sidewall of the heat-absorbing portion 52 is greatly increased, whereby turbulence is generated when the liquid flows through the inner sidewall of the heat-absorbing portion 52. Thus, the liquid can sufficiently contact the inner sidewalls of the heat-absorbing portion 52. Accordingly, the heat exchange efficiency between the heat-absorbing portion 52 and the liquid is improved.

Referring to FIGS. 6-7, a liquid-cooling device in accordance with a third exemplary embodiment of the disclosure is shown. The difference between this embodiment and the previous embodiment is that the liquid cooling device comprises a heat exchanger 70 and a liquid-guiding component 60 engaging with the heat exchanger 70. The heat exchanger 70 comprises a base plate 71 and a heat-absorbing portion 72 protruding downwardly and perpendicularly from the base plate 71. The heat-absorbing portion 72 defines a plurality of annular grooves 720 in an inner sidewall along a circumference thereof, for enhancing a roughness of the inner sidewall of the heat-absorbing portion 72 and increasing a contacting area between the liquid and the inner sidewall of the heat-absorbing portion 72. The liquid-guiding component 60 comprises a hollow body 62 defining an inlet 620 at a top end thereof and an annular flange 64 extending from the body 62. The annular flange 64 defines a plurality of spaced outlets 640 therein around the body 62. The first liquid passage 100 is defined through the body 62 of the liquid-guiding component 60. The second liquid passage 200 is defined between an outer sidewall of the body 62 of the liquid-guiding component 60 and the inner sidewall of the heat-absorbing portion 72. The body 62 has a cylindrical configuration with a gradually decreased cross section from top to bottom thereof, whereby the second liquid passage 200 has a cross section gradually increased from top to bottom of the heat-absorbing portion 72. The body 62 of the liquid-guiding component 60 functions as a tapered nozzle, which is inserted into the heat-absorbing portion 72 to impinge the liquid onto a center of the bottom of the heat-absorbing portion 72 and increase the jet speed of the liquid in entering the second liquid passage 200.

In operation, the liquid firstly enters the first liquid passage 100 via the inlet 620, travels in the second liquid passage 200 through a bottom of an inside of the heat-absorbing portion 72, then leaves the heat-absorbing portion 72 from the outlet 640 to take away heat in the heat-absorbing portion 72.

According to the configuration of the body 62 with a gradually decreased cross section from top to bottom of the heat-absorbing portion 72, when a jet impinges on the bottom surface of heat-absorbing portion 72, a hydrodynamic and thermal boundary layer is very quickly formed in the impingement region due to high jet acceleration and increase in pressure. Consequently, an extremely high heat transfer coefficient is obtained within the impingement region to optimize the heat exchanging efficiency of the liquid.

It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1 A liquid-cooling device, comprising: a heat exchanger comprising a bottom face adapted for contacting an electronic device, the heat exchanger defining a cavity over the bottom face thereof; and a liquid-guiding component comprising a hollow body defining a first liquid passage therethrough and a fixing portion engaging with the heat exchanger, the body being disposed in the cavity and spaced from a bottom of the cavity of the heat exchanger, a second liquid passage being defined between an outer periphery of the body and an inner sidewall of the heat exchanger surrounding the cavity, the second liquid passage being in fluid communication with the first liquid passage via the bottom of the cavity; wherein an outlet and an inlet are formed at one end of the liquid-guiding component distant from the bottom of the cavity, the outlet and inlet being in fluid communication with the cavity of the heat exchanger, whereby cooling liquid enters the cavity via the inlet, passes through the first and second liquid passages and leaves the cavity via the outlet.
 2. The liquid-cooling device as claimed in claim 1, wherein the fixing potion extends outwardly from the body and abuts against an inner sidewall of the heat exchanger surrounding the cavity.
 3. The liquid-cooling device as claimed in claim 2, wherein the fixing portion comprises an annular flange extending outwardly from a circumference of the body and an outer edge of the annular flange abutting against the inner sidewall of the heat exchanger surrounding the cavity.
 4. The liquid-cooling device as claimed in claim 2, wherein the heat exchanger defines a fixing slot surrounding the cavity and the fixing portion is received in the fixing slot to be secured to the heat exchanger.
 5. The liquid-cooling device as claimed in claim 4, wherein the heat exchanger comprises a base plate and a heat-absorbing portion extending from the base plate to contact the electronic device and the cavity is defined in the heat-absorbing portion.
 6. The liquid-cooling device as claimed in claim 5, wherein the fixing portion of the liquid-guiding component defines the inlet and the body defines the outlet at an end thereof, the inlet and the outlet are respectively in fluid communication with the second and first liquid passages.
 7. The liquid-cooling device as claimed in claim 5, wherein the body of the liquid-guiding component has a gradually decreased cross section along a direction remote from the base plate of the heat exchanger, the inlet and the outlet being in fluid communication with the first and second liquid passages, respectively.
 8. The liquid-cooling device as claimed in claim 7, wherein the heat exchanger defines an annular groove in the inner sidewall surrounding the cavity.
 9. The liquid-cooling device as claimed in claim 1, wherein the liquid-guiding component comprises a fixing plate engaging an inner sidewall of the heat exchanger surrounding the cavity and the inlet is formed between an outer edge of the fixing plate and the inner sidewall of the heat exchanger.
 10. The liquid-cooling device as claimed in claim 9, wherein the heat exchanger defines a fixing slot surrounding the cavity and the fixing plate of the liquid-guiding component is received in the fixing slot with a gap therebetween, whereby a third liquid passage being defined between a lower surface of the fixing plate and a bottom of the fixing slot and in fluid communicated with the inlet and the second liquid passage.
 11. The liquid-cooling device as claimed in claim 10, wherein the heat exchanger comprises a base plate defining the fixing slot surrounding the cavity and a heat-absorbing portion extending from the base plate, the cavity being defined in the heat-absorbing portion.
 12. The liquid-cooling device as claimed in claim 11, wherein the fixing plate of the liquid-guiding component comprises a plurality of spaced tongues engaging an inner sidewall of the base plate of the heat exchanger.
 13. The liquid-cooling device as claimed in claim 12, wherein the fixing plate of the liquid-guiding component is spaced from a bottom of the of the fixing slot and has a thickness smaller that a depth of the fixing slot. 